The present invention relates to a single roller concrete finishing machine, which can finish the surface of concrete roads, pavements, sidewalks, floors, platforms, etc., in a smooth texture.
Concrete finishing goes back many decades and various roller devices have been used to effect a screeding, or finishing of the concrete material in a given area. Many of these machines are designed to operate on rails (screeds) or form walls and are utilized to effect a leveling of the unset concrete within the form. Typically, grading and finishing work has been accomplished by hand operated screeds or trowels. However, manual operations have made grading and finishing of concrete surfaces time consuming and expensive.
In attempting to ease the time and cost burdens in grading and finishing concrete surfaces, powered, roller-type screeds are used to finish a surface in order to make it level and smooth.
Conventional powered, roller-type screeds such as the device disclosed in Mitchell, U.S. Pat. No. 4,142,815, includes a counter-rotating elongated roller with a manually movable support frame connected to only one end of the roller to allow push-pull control of the roller by an operator from one side of the form, with a motor mounted on the support frame and connected to drive the roller. Mitchell suffers from the problem exhibited by the prior art, in that it still takes a great deal of manual effort to move the device. Further, control of the support frame, whose movement has a direct effect on the movement of the roller, is difficult, even with another manual pull device coupled to the opposite end of the roller to allow auxiliary pull control of the roller.
Other prior art devices, such as Turck, U.S. Pat. No. 5,803,656, and Owens U.S. Pat. No. 4,752,156, disclose a walk-behind chassis, with the chassis in Turck being attached to a roller. In both cases, the walk-behind chassis makes the working conditions for the operators difficult, as well as control of the screeds harder to operate.
Still other conventional powered roller-type screed apparatuses, such as Allen, U.S. Pat. No. 4,702, 640, and Owens U.S. Pat. No. 5,062,738, disclose portable screeds with operator units at each end of the screed. However, in Allen, a winch system is used to facilitate uphill and downhill translation of the concrete finisher on a sloping concrete surface, and enables the system to be operated by one person. The addition of the winch system makes the powered roller-type screed apparatus more complicated.
As for Owens, the device in Owens uses an elongated screed plate which has a pair of control bars mounted so that operators may guide the screed over a concrete surface contained between a pair of forms. However, the screed plate is connected to a stiffening brace (i.e., chassis), and the brace includes a longitudinal concave scoop extending the length of its facing side for collecting excess concrete as the screed is drawn along the concrete. This concave scoop complicates the machinery and makes it more difficult to handle.
Thus, all the prior art single roller concrete finishing machines suffer from the same deficiencies, in that they complicate the machinery and make the finishing of the concrete surface difficult for the operators.
An object of the present invention is to provide a powered single roller concrete finishing machine, which can finish a concrete surface, but which has a simple mechanical construction.
In fulfilling the above objectives, the present invention includes a concrete finishing machine having a primary motorized unit and a secondary unmotorized unit disposed on each side of a surface to be paved, with a single roller disposed on the unfinished surface which connects the primary unit and the secondary unit. The primary unit includes a first base having an elongated first handle having two ends, one end of the first handle being connected to the first base, and the other end of the first handle being connected to handlebars, below which an engaging lever is disposed. The secondary unit includes a second base with an elongated second handle similar to the first handle, but without the engaging lever. The handles of each of the primary unit and the secondary unit are swingably adjustable in a horizontal plane to aid in the leveling of the concrete surface to be finished. The primary unit has an engine mounted on the first base, and a mechanism to rotate the roller. When the engine is turned on, the roller does not rotate. Only when the engaging lever is pressed, does the roller tube rotate, so that the forward motion of the concrete finishing machine, coupled with the pulling backward motion of the operator and helper, can level the concrete. The roller is stopped from rotating when the engaging lever is released.
When the primary and secondary units are not in use, they rest on an adjustable foot which protrudes downwardly from a rear side of the handle. When the primary unit and the secondary unit are not connected to the roller, they can be moved by lifting the handle onto a pair of wheels disposed at a front of each of the units.
These and other objects and advantages of the present invention will become apparent in the course of the following description.